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Author Topic:   General Relativity.
RoyLennigan
Inactive Member


Message 31 of 129 (246656)
09-26-2005 8:20 PM
Reply to: Message 29 by Ben!
09-26-2005 12:53 PM


Re: Light and Energy
quote:
There are two concepts of intensity; one is independent of US, independent of our ability to SEE the light with our very own eyes. That is the sense in which intenisity is being used here (we are, after all, talking physics here). You're talking PSYCHOPHYSICS. PSYCHOPHYSICS is different, Roy. This thread is not about General Relativity in Psychophysics. It's about General Relativity.
i know that, thats what i was saying in my post. it seemed to me that madeofstarstuff was talking about how we see light. i was trying to say that how we see light is not how all light actally is. so basically you and i are in agreement.
please re-read my post with how it pertains to the two subjects:
"the energy, or wavelength, of a photon determines the frequency of the light (physics). the frequency of light determines the intensity of how we see that light (psychophysics). but the higher or lower the frequency doesnt always mean a more or less visible intense light (psychophysics). it entails a more or less actual intensity (physics). there are other aspects to light than what we see with our own eyes(ppsychophysics). photons all move at the speed of light(physics). but depending on the wavelength of the photon, we see it differently(psycophysics). there is a small spectrum of light that we can view, everything else is invisible to us(anatomy . that is why an x-ray would appear to be weaker, but is in fact very intense."

This message is a reply to:
 Message 29 by Ben!, posted 09-26-2005 12:53 PM Ben! has not replied

Replies to this message:
 Message 33 by madeofstarstuff, posted 09-27-2005 11:07 AM RoyLennigan has replied

  
RoyLennigan
Inactive Member


Message 32 of 129 (246657)
09-26-2005 8:25 PM
Reply to: Message 30 by 1.61803
09-26-2005 1:08 PM


Re: Light and Energy
quote:
First off no one knows what energy is.
Secondly the energy is a result of the affects the photons have on matter. IE: electrons making quantum jumps within the valances. The greater the frequency the greater the excitation of atoms, which gives off the energy as heat and light.
The element affected will determine what jumps and this will determine what color the light is.
Amplitude will determine how bright this light is.
Of course this could all be wrong as I am drawing on 30 year old information.
i think you're pretty much right. but brightness is a part of psychophysics. there is photon intensity, which relates to the frequency, but it can only be viewed as brightness in the visible spectrum. a gamma ray has the most intensity, but we cannot see it because the wavelengths are too small.

This message is a reply to:
 Message 30 by 1.61803, posted 09-26-2005 1:08 PM 1.61803 has not replied

  
madeofstarstuff
Member (Idle past 5960 days)
Posts: 47
Joined: 08-12-2005


Message 33 of 129 (246701)
09-27-2005 11:07 AM
Reply to: Message 31 by RoyLennigan
09-26-2005 8:20 PM


Re: Light and Energy
I was talking about individual photons, as was Ben, I believe. I thought the photoelectric effect showed that the energy of light is directly related to its frequency and comes in packets. If you crank up the intensity of low energy (low frequency) light you don't get electrons. If you increase the frequency, remaining at a low intensity, you get electrons. If you increase the intensity of high frequency light, you get more electrons. Higher frequencies of the same intensity give you faster moving electrons. This is how I thought it worked. As for the intensity of an individual photon, I've never come to an understanding of this idea. Perhaps this is where I am misunderstanding.
I must have misread someones post originally as it all seems fairly correct now that I reread it. Either way, this really has nothing to do with the intent of Ben's question in the first place.

This message is a reply to:
 Message 31 by RoyLennigan, posted 09-26-2005 8:20 PM RoyLennigan has replied

Replies to this message:
 Message 34 by RoyLennigan, posted 09-27-2005 3:36 PM madeofstarstuff has replied

  
RoyLennigan
Inactive Member


Message 34 of 129 (246760)
09-27-2005 3:36 PM
Reply to: Message 33 by madeofstarstuff
09-27-2005 11:07 AM


Re: Light and Energy
just to clear some things up, i think none of us really completely understand photons, including me.
from wikipedia:
"In physics, the photon is a quantum of the electromagnetic field, for instance light...
The photon is one of the elementary particles. Its interactions with electrons and atomic nuclei account for a great many of the features of matter, such as the existence and stability of atoms, molecules, and solids. These interactions are studied in quantum electrodynamics (QED), which is the oldest part of the Standard Model of particle physics.
In some respects a photon acts as a particle, for instance when registered by the light sensitive device in a camera. In other respects, a photon acts like a wave, as when passing through the optics in a camera. According to the so-called wave-particle duality in quantum physics, it is natural for the photon to display either aspect of its nature, according to the circumstances. Normally, light is formed from a large number of photons, with the intensity or brightness related to the number of them. At low intensity, it requires very sensitive instruments, used in astronomy or spectroscopy, for instance, to detect the individual photons..."
Photon - Wikipedia
as for ben's question, after reading this article i think i can shed some light on the subject (no pun intended)
quote:
If the frequency of light is really just a statement about it's probability amplitude, then how is it that light's energy is related to it's frequency? It seems pretty straightforward to say that light's energy is then related to it's probability amplitude (and how often that little complex vector is spinning). Why would faster spinning of that little vector mean higher energy?
The frequency of light is a "measurement of the number of times that a repeated event occurs per unit time,"(1) or the measurement of oscillations per second, in the usual case. the frequency of a photon is inversely proportional to the wavelength; the higher the frequency, the shorter the wavelength. The wavelength is the length between a crest and the next crest of a wave, or the "distance between repeating units of a wave pattern."(2) The amplitude of a wave is the "magnitude of the maximum disturbance in the medium during one wave cycle," (3) or the 'height' of a wave on a graph.
a diagram depicting the wavelength, frequency and amplitude:
1) Frequency - Wikipedia
2) Wavelength - Wikipedia
3) Amplitude - Wikipedia

This message is a reply to:
 Message 33 by madeofstarstuff, posted 09-27-2005 11:07 AM madeofstarstuff has replied

Replies to this message:
 Message 35 by madeofstarstuff, posted 09-28-2005 12:06 AM RoyLennigan has replied

  
madeofstarstuff
Member (Idle past 5960 days)
Posts: 47
Joined: 08-12-2005


Message 35 of 129 (246856)
09-28-2005 12:06 AM
Reply to: Message 34 by RoyLennigan
09-27-2005 3:36 PM


Re: Light and Energy
The picture you chose here lays it all out. The way I understand it is as follows, someone tell me where, if I am wrong. The energy associated with any given single, solitary photon is related to its frequency, and also varies with varying frequencies. A coherent (completely in phase and of the same frequency) light wave (many photons) oscillates at some frequency with its amplitude defined as the number of photons in that wave having the same frequency. The amplitude of a light wave is the intensity of that light wave. Inquiring about the amplitude of a photon is the same as inquiring about the intensity of a photon. I would assume from this (perhaps this is where I misunderstand) that the intensity of any individual photon, regardless of it frequency, is the same, namely one (choose your unit of measure) photon. This is where I come to the understanding that the energy of a photon corresponds to its frequency and has nothing to do with its intensity since intensity is the same for any one photon.
This message has been edited by madeofstarstuff, 09-28-2005 12:07 AM
This message has been edited by madeofstarstuff, 09-28-2005 12:11 AM

This message is a reply to:
 Message 34 by RoyLennigan, posted 09-27-2005 3:36 PM RoyLennigan has replied

Replies to this message:
 Message 36 by RoyLennigan, posted 09-28-2005 11:55 AM madeofstarstuff has replied

  
RoyLennigan
Inactive Member


Message 36 of 129 (246953)
09-28-2005 11:55 AM
Reply to: Message 35 by madeofstarstuff
09-28-2005 12:06 AM


Re: Light and Energy
i think i see what you are saying. i dont really know much about photons, but in my work with sound waves, the amplitude does correspond to the energy, or the volume of a sound. i would assume the same goes for light. also, it takes more energy to create a higher amplitude.
none of these terms correspond to how many photons there are in a light wave, though. the frequency, amplitude, and wavelength can all be applied to a single photon or many photons. say a single photon is travelling through space. we observe the photon and see that its oscillations repeat every one second, therefore it has a frequecy of 1Hz. Its wavelength can be determined by dividing the speed of the wave type (here, the speed of light) by the frequency of the wave (here, 1Hz). The amplitude is a bit more difficult, but it basically measures the energy of the wave. Intensity of a wave is the average fluctuation of energy through time. It is the energy per unit volume divided by the velocity of that energy.
Intensity - Wikipedia
This message has been edited by RoyLennigan, 09-28-2005 11:55 AM

This message is a reply to:
 Message 35 by madeofstarstuff, posted 09-28-2005 12:06 AM madeofstarstuff has replied

Replies to this message:
 Message 38 by madeofstarstuff, posted 09-28-2005 2:48 PM RoyLennigan has replied

  
1.61803
Member (Idle past 1534 days)
Posts: 2928
From: Lone Star State USA
Joined: 02-19-2004


Message 37 of 129 (246977)
09-28-2005 1:50 PM


Dr. Milo Wolff discovered that the duality of light confounding the ability to associate vectors in the particulate photon was solved in 1986. I will quote a summary written by him in 1990 which Ben may find of interest.
Dr. Milo Wolff writes:
The Wave Structure of fundamental Particles evolved over five years. It began with a simple speculation that waves in Space could explain the de Broglie wavelength. It continued to agree with more laws and observations than I first expected and I was amazed. The 'Particle' is two identical spherical waves travelling radially in opposite directions so that together they form a spherical standing wave.The wave which travels inward towards the center is called an In-Wave, and the wave travelling outward is an Out-Wave. The nominal location of the 'Partical' is the Wave-Center, but as must be true for any charged Particle, it has presence everywhere in Space because the charged forces extend throughout the Universe.
How do Solid Bodies form from Waves?-The solid crystal array is a matrix of atoms held rigidly in space. How are the atoms suspended in space? We must conclude that the crystal's rigidity derives from fixed standing waves propagating in a rigid wave medium.Calculations for diamonds and nuclear structure yields an enormous rigidity. This is really a separate argument about the rigidity of space, which is one of its properties.
What is a Light 'Photon'? -Two Spherical Standing Waves
(SSW) oscillators exchange energy much like classical coupled oscillators, such as electric circuits or joined pendulums. The coupling provided by the non-linear centers of the resonances (high Wave-Density Wave - Centers) allows them to shift frequency patterned by the modulation of each other's In and Out-Waves. Since significant coupling can only occure between two oscillators which possess the same resonant elements, the frequency (energy) take place between two resonances, energy seems to be transported from the center of one resonance to another. We observe a loss of energy where frequency decreases and added energy where it increases. The exchange appears to travel with the speed of the In-Waves of the receiving resonance which is c, the velocity of light. When large numbers of changes occure together, we can sample part of it and see a beam of light (which causes the continuous electromagnetic waves of Modern Physics). When single exchanges occure we see 'photons' as discrete Standing Wave interactions. Thus the transitory modulated waves travelling between two resonances create the illusion of the 'photon particle'.

Replies to this message:
 Message 41 by RoyLennigan, posted 09-28-2005 3:35 PM 1.61803 has replied

  
madeofstarstuff
Member (Idle past 5960 days)
Posts: 47
Joined: 08-12-2005


Message 38 of 129 (246994)
09-28-2005 2:48 PM
Reply to: Message 36 by RoyLennigan
09-28-2005 11:55 AM


Re: Light and Energy
RL:
the amplitude does correspond to the energy, or the volume of a sound
What is the volume of a photon? It seems intuitively obvious that a single photon should have an amplitude. Most things in this realm, however, go against some level of intuition. I just don't see, given the results of the photoelectric effect, how intensity/amplitude should differ between one photon of one frequency and any other photon of any other frequency? I further conclude that the energy of a photon is independent of its intensity/amplitude?
Why this is so, and what frequency and energy have to do with one another outside of just saying that E=hf, is what Ben is asking about, I assume.
The amplitude is a bit more difficult, but it basically measures the energy of the wave.
If amplitude and intensity are synonymous in your usage here, then you have to adopt a different understanding of light due to the results of Einstein's work on the photoelectric effect.

This message is a reply to:
 Message 36 by RoyLennigan, posted 09-28-2005 11:55 AM RoyLennigan has replied

Replies to this message:
 Message 39 by 1.61803, posted 09-28-2005 3:00 PM madeofstarstuff has replied
 Message 40 by RoyLennigan, posted 09-28-2005 3:16 PM madeofstarstuff has replied

  
1.61803
Member (Idle past 1534 days)
Posts: 2928
From: Lone Star State USA
Joined: 02-19-2004


Message 39 of 129 (246997)
09-28-2005 3:00 PM
Reply to: Message 38 by madeofstarstuff
09-28-2005 2:48 PM


Re: Light and Energy
madeofstarstuff writes:
Why this is so, and what frequency and energy have to do with one another outside of just saying that E=hf, is what Ben is asking about, I assume.
Please read the above summary by Dr. Wolff as it addresses this very relationship quite concisley IMO. edit typo.**
This message has been edited by 1.61803, 09-28-2005 03:01 PM

This message is a reply to:
 Message 38 by madeofstarstuff, posted 09-28-2005 2:48 PM madeofstarstuff has replied

Replies to this message:
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RoyLennigan
Inactive Member


Message 40 of 129 (247002)
09-28-2005 3:16 PM
Reply to: Message 38 by madeofstarstuff
09-28-2005 2:48 PM


Re: Light and Energy
quote:
What is the volume of a photon? It seems intuitively obvious that a single photon should have an amplitude. Most things in this realm, however, go against some level of intuition. I just don't see, given the results of the photoelectric effect, how intensity/amplitude should differ between one photon of one frequency and any other photon of any other frequency? I further conclude that the energy of a photon is independent of its intensity/amplitude?
analogous to sound, the 'volume' of a photon would be the amplitude, or the energy of the wave/particle. a single photon does have amplitude, just as many photons have amplitude. intensity and amplitude (in physics) are entirely different things. amplitude relates to how much energy the wave has, while intensity relates to the overall fluctuation of that energy per unit of time. i don't really know how the amplitude of one frequency differs from another. from what i've read it would seem that two different frequencies could have the same amplitude, yet have different intensities. the energy of a photon is definately not independant of its amplitude, seeing as amplitude is just a unit for measurement of energy.
quote:
If amplitude and intensity are synonymous in your usage here, then you have to adopt a different understanding of light due to the results of Einstein's work on the photoelectric effect.
amplitude and intensity are not synonymous, especially in my usage here. in my previous posts i was ignorant to the definition of intensity in physics, but i have since read into it.
"In physics, the word "intensity" is not synonymous with "strength", "amplitude", or "level", as it sometimes is in colloquial speech.
"intensity is a measure of the time-averaged energy flux. To find the intensity, take the energy density (that is, the energy per unit volume) and multiply it by the velocity at which the energy is moving. The resulting vector has the units of power divided by area (i.e. watt/m)."
Intensity - Wikipedia

This message is a reply to:
 Message 38 by madeofstarstuff, posted 09-28-2005 2:48 PM madeofstarstuff has replied

Replies to this message:
 Message 44 by madeofstarstuff, posted 09-28-2005 8:36 PM RoyLennigan has replied

  
RoyLennigan
Inactive Member


Message 41 of 129 (247009)
09-28-2005 3:35 PM
Reply to: Message 37 by 1.61803
09-28-2005 1:50 PM


would this diagram refer to what you are talking about, 1.61803?

This message is a reply to:
 Message 37 by 1.61803, posted 09-28-2005 1:50 PM 1.61803 has replied

Replies to this message:
 Message 42 by 1.61803, posted 09-28-2005 3:50 PM RoyLennigan has not replied
 Message 45 by madeofstarstuff, posted 09-28-2005 8:58 PM RoyLennigan has not replied

  
1.61803
Member (Idle past 1534 days)
Posts: 2928
From: Lone Star State USA
Joined: 02-19-2004


Message 42 of 129 (247018)
09-28-2005 3:50 PM
Reply to: Message 41 by RoyLennigan
09-28-2005 3:35 PM


Sure, here is a link that may be of interest in regard to light. Electromagnetic Radiation

This message is a reply to:
 Message 41 by RoyLennigan, posted 09-28-2005 3:35 PM RoyLennigan has not replied

  
madeofstarstuff
Member (Idle past 5960 days)
Posts: 47
Joined: 08-12-2005


Message 43 of 129 (247041)
09-28-2005 4:52 PM
Reply to: Message 39 by 1.61803
09-28-2005 3:00 PM


Re: Light and Energy
Yes, I realize that, and it is way over my head! I tried picturing it, but still couldn't completely get my ind around it. I will have to reread again.

This message is a reply to:
 Message 39 by 1.61803, posted 09-28-2005 3:00 PM 1.61803 has not replied

  
madeofstarstuff
Member (Idle past 5960 days)
Posts: 47
Joined: 08-12-2005


Message 44 of 129 (247088)
09-28-2005 8:36 PM
Reply to: Message 40 by RoyLennigan
09-28-2005 3:16 PM


Re: Light and Energy
"To find the intensity, take the energy density (that is, the energy per unit volume) and multiply it by the velocity at which the energy is moving."
Taking this to heart, then seeing as though the energy of a photon is dependent upon its frequency, and the velocity of light is constant, then for the same intensity of varying frequencies the energy of the light is varying as well. Another indicator of intensity of light not influencing the energy of that light.
"The term intensity has a particular meaning here: it is the number of waves or photons of light reaching your detector; a brighter object is more intense but not necessarily more energetic. Remember that a photon's energy depends on the wavelength (or frequency) only, not the intensity."
from Electromagnetic Radiation
This site specifies that energy is dependent upon the frequency only, no mention of amplitude. Nowhere can I find a description of the amplitude of a single photon. This is all very interesting as I have never thought of all of this in this way. I am familiar with the self-sustaining, propogating, electric and magnetic fields, as that is what a beam of light is. I never thought they were in phase as it appears to be shown in the latest picture, I thought they were ninety degrees out of phase as well as ninety degrees perpendicular. Oh well.
Any help on finding something regarding the amplitude of a photon particularly would make me feel better, as the only thing I see is in regards to Intensity = amplitude^2, which requires many photons, as I see it.
This message has been edited by madeofstarstuff, 09-28-2005 08:41 PM

This message is a reply to:
 Message 40 by RoyLennigan, posted 09-28-2005 3:16 PM RoyLennigan has replied

Replies to this message:
 Message 46 by RoyLennigan, posted 09-29-2005 2:05 AM madeofstarstuff has replied

  
madeofstarstuff
Member (Idle past 5960 days)
Posts: 47
Joined: 08-12-2005


Message 45 of 129 (247093)
09-28-2005 8:58 PM
Reply to: Message 41 by RoyLennigan
09-28-2005 3:35 PM


One more time
I have also found this:
Photon energy is inversely proportional to photon wave length; the shorter the wavelength, the greater the energy. Since photon speed through space is a constant, shorter wavelengths must pass a point in space in less time than longer wave lengths. Because of this, and the fact that the maximum possible electric and magnetic amplitude of any point in space is a certain finite value, photon action, expressed as Joule-seconds is a constant for all photons regardless of frequency. Planck's constant is this amount of electromagnetic amplitude available at any one point in space. Note that it is not a property of a photon, but rather a property of space itself. It is therefore not only the maximum amount but also the minimum amount of action available for a photon in space.
at this location: http://members.aol.com/photonics/willis.htm#Amplitude
I would have only linked the website if it were short, however, this was pretty far down the page. This says that the amplitude for every frequency of every individual photon is the same. Does this seem right?

This message is a reply to:
 Message 41 by RoyLennigan, posted 09-28-2005 3:35 PM RoyLennigan has not replied

  
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